Significance

Food choice can serve as a social shibboleth, whereby information about what an individual eats affords insight into her cultural background and social relationships. We provide evidence for an early-emerging system linking food preferences to social identity. Infants expect people to share food preferences, unless those people belong to different groups, suggesting human reasoning about food preferences is fundamentally social. However, infants generalize disgust toward a food even across people who belong to different groups, suggesting that infants are particularly vigilant to social information that might signal danger. This research opens new lines of investigation regarding infant social cognition and food selection across the lifespan, and has implications for social policy surrounding nutrition, heath, and obesity.

Abstract

Selecting appropriate foods is a complex and evolutionarily ancient problem, yet past studies have revealed little evidence of adaptations present in infancy that support sophisticated reasoning about perceptual properties of food. We propose that humans have an early-emerging system for reasoning about the social nature of food selection. Specifically, infants’ reasoning about food choice is tied to their thinking about agents’ intentions and social relationships. Whereas infants do not expect people to like the same objects, infants view food preferences as meaningfully shared across individuals. Infants’ reasoning about food preferences is fundamentally social: They generalize food preferences across individuals who affiliate, or who speak a common language, but not across individuals who socially disengage or who speak different languages. Importantly, infants’ reasoning about food preferences is flexibly calibrated to their own experiences: Tests of bilingual babies reveal that an infant’s sociolinguistic background influences whether she will constrain her generalization of food preferences to people who speak the same language. Additionally, infants’ systems for reasoning about food is differentially responsive to positive and negative information. Infants generalize information about food disgust across all people, regardless of those people’s social identities. Thus, whereas food preferences are seen as embedded within social groups, disgust is interpreted as socially universal, which could help infants avoid potentially dangerous foods. These studies reveal an early-emerging system for thinking about food that incorporates social reasoning about agents and their relationships, and allows infants to make abstract, flexible, adaptive inferences to interpret others’ food choices.

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